This invention relates generally to simulating and optimizing land seismic survey operations. More particularly, the invention is a method and system for simulating and optimizing seismic surveys by applying operations research methodologies to the land seismic surveying problem domain.
Land seismic surveys are typically conducted over large geographical areas (tens to hundreds of square kilometers). These surveys take anywhere from a few days to a few years with crews ranging from 20 to 1000 people, requiring capital equipment valued in the tens of millions of dollars, and generating survey revenues ranging from tens to hundreds of millions of dollars. The challenge is to bid on, plan for and conduct these large, complicated and expensive projects in a profitable manner. When we use the term "land seismic survey", it includes purely land operations as well as the "transition zone seismic surveys" which can involve swamps, shallow waters, and nearshore operations.
The invention combines and enhances technologies to improve the profitability of land seismic surveys. Surveys are tending to be larger, involve new technologies, occur in mature oilfields containing pipelines and other structures and are executed under tight financial controls. Advances in airborne and satellite imaging technology are exploited to produce terrain maps with locations classified in terms meaningful to the planning and execution of the survey. Advanced visualization and virtual environment technology is used to view the information. Discrete event simulation is used to evaluate different options for executing the survey, producing time and risk estimates for particular equipment and personnel configurations, and also enabling "what-if" scenario analysis to improve decision-making. Mathematical optimization technologies are used to enhance the efficiency of the job execution via optimal route planning and other logistical components. The invention can be used throughout the life cycle of the land seismic survey to simulate and optimize the operations: beginning with the bidding and planning phase through the execution of the land seismic survey itself and also during post-job operational analysis.
The invention exploits technological advances by using high resolution or satellite digital imagery and processing the digital data from that imagery to produce high resolution terrain elevation maps and store that data in a Geographic Information System (GIS). Discrete event simulation techniques then are used to run simulations and model the land seismic survey operations. Various aspects can be optimized using mathematical programming techniques. The simulation and optimization can be done prior to the actual conduct of the land seismic operation for the purposes of planning and bidding. It can also be done while the survey is being executed, for example to solve and provide an optimal solution for a problem encountered during the operation itself.
Currently in land seismic surveys, the primary tools used to support bidding, planning and execution are spreadsheets and aerial photographs. Discrete event simulation techniques have been applied in the manufacturing domain and in the design of electronic systems but have not generally been applied to the outdoor, unstructured environment of land seismic surveys. Military war-gaming and civil engineering construction projects to some extent have used discrete event simulation in the outdoor environment. This invention adds the complex, specialized behaviors of the components in a land seismic survey; explicit economic considerations; and integrated ability to perform structured what-if analyses of the survey's likely operational performance for particular tactical decisions (such as equipment and crew mix). Compared to the state-of-the-art spreadsheet, the present invention is able to explicitly account for dynamic behaviors.
Satellite and airborne digital imagery and digital terrain maps have also been used by military and civil authorities for some time. For a land seismic survey a much higher resolution is needed than has been used in the past, on the order of two meter by two meter image elements, and vertical resolution of about the same. Imagery of this quality is only now becoming commercially available. This invention exploits multi-spectral, laser and radar imagery combined with surface geology knowledge to provide surface classification. These techniques have been in use before (e.g., LandSat images for crop health) but not at the resolutions needed, in both the spatial resolution and classification senses. Lastly, the use of optimization techniques for route planning and logistics are widely known. The majority of the published work deals only with deterministic planning, and does not accommodate stochastic behaviors. This invention includes the ability to improve the logistics (including site selection and route planning) of a land seismic survey, including stochastic behaviors, using simulation and optimization techniques.